The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/netinet6/nd6.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*      $FreeBSD: releng/5.0/sys/netinet6/nd6.c 101240 2002-08-02 20:49:14Z rwatson $   */
    2 /*      $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $   */
    3 
    4 /*
    5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
    6  * All rights reserved.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  * 3. Neither the name of the project nor the names of its contributors
   17  *    may be used to endorse or promote products derived from this software
   18  *    without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
   21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
   24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   30  * SUCH DAMAGE.
   31  */
   32 
   33 /*
   34  * XXX
   35  * KAME 970409 note:
   36  * BSD/OS version heavily modifies this code, related to llinfo.
   37  * Since we don't have BSD/OS version of net/route.c in our hand,
   38  * I left the code mostly as it was in 970310.  -- itojun
   39  */
   40 
   41 #include "opt_inet.h"
   42 #include "opt_inet6.h"
   43 #include "opt_mac.h"
   44 
   45 #include <sys/param.h>
   46 #include <sys/systm.h>
   47 #include <sys/callout.h>
   48 #include <sys/mac.h>
   49 #include <sys/malloc.h>
   50 #include <sys/mbuf.h>
   51 #include <sys/socket.h>
   52 #include <sys/sockio.h>
   53 #include <sys/time.h>
   54 #include <sys/kernel.h>
   55 #include <sys/protosw.h>
   56 #include <sys/errno.h>
   57 #include <sys/syslog.h>
   58 #include <sys/queue.h>
   59 #include <sys/sysctl.h>
   60 
   61 #include <net/if.h>
   62 #include <net/if_dl.h>
   63 #include <net/if_types.h>
   64 #include <net/if_atm.h>
   65 #include <net/fddi.h>
   66 #include <net/route.h>
   67 
   68 #include <netinet/in.h>
   69 #include <netinet/if_ether.h>
   70 #include <netinet6/in6_var.h>
   71 #include <netinet/ip6.h>
   72 #include <netinet6/ip6_var.h>
   73 #include <netinet6/nd6.h>
   74 #include <netinet6/in6_prefix.h>
   75 #include <netinet/icmp6.h>
   76 
   77 #include <net/net_osdep.h>
   78 
   79 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
   80 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
   81 
   82 #define SIN6(s) ((struct sockaddr_in6 *)s)
   83 #define SDL(s) ((struct sockaddr_dl *)s)
   84 
   85 /* timer values */
   86 int     nd6_prune       = 1;    /* walk list every 1 seconds */
   87 int     nd6_delay       = 5;    /* delay first probe time 5 second */
   88 int     nd6_umaxtries   = 3;    /* maximum unicast query */
   89 int     nd6_mmaxtries   = 3;    /* maximum multicast query */
   90 int     nd6_useloopback = 1;    /* use loopback interface for local traffic */
   91 int     nd6_gctimer     = (60 * 60 * 24); /* 1 day: garbage collection timer */
   92 
   93 /* preventing too many loops in ND option parsing */
   94 int nd6_maxndopt = 10;  /* max # of ND options allowed */
   95 
   96 int nd6_maxnudhint = 0; /* max # of subsequent upper layer hints */
   97 
   98 #ifdef ND6_DEBUG
   99 int nd6_debug = 1;
  100 #else
  101 int nd6_debug = 0;
  102 #endif
  103 
  104 /* for debugging? */
  105 static int nd6_inuse, nd6_allocated;
  106 
  107 struct llinfo_nd6 llinfo_nd6 = {&llinfo_nd6, &llinfo_nd6};
  108 static size_t nd_ifinfo_indexlim = 8;
  109 struct nd_ifinfo *nd_ifinfo = NULL;
  110 struct nd_drhead nd_defrouter;
  111 struct nd_prhead nd_prefix = { 0 };
  112 
  113 int nd6_recalc_reachtm_interval = ND6_RECALC_REACHTM_INTERVAL;
  114 static struct sockaddr_in6 all1_sa;
  115 
  116 static void nd6_slowtimo __P((void *));
  117 static int regen_tmpaddr __P((struct in6_ifaddr *));
  118 
  119 struct callout nd6_slowtimo_ch;
  120 struct callout nd6_timer_ch;
  121 extern struct callout in6_tmpaddrtimer_ch;
  122 
  123 void
  124 nd6_init()
  125 {
  126         static int nd6_init_done = 0;
  127         int i;
  128 
  129         if (nd6_init_done) {
  130                 log(LOG_NOTICE, "nd6_init called more than once(ignored)\n");
  131                 return;
  132         }
  133 
  134         all1_sa.sin6_family = AF_INET6;
  135         all1_sa.sin6_len = sizeof(struct sockaddr_in6);
  136         for (i = 0; i < sizeof(all1_sa.sin6_addr); i++)
  137                 all1_sa.sin6_addr.s6_addr[i] = 0xff;
  138 
  139         /* initialization of the default router list */
  140         TAILQ_INIT(&nd_defrouter);
  141 
  142         nd6_init_done = 1;
  143 
  144         /* start timer */
  145         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
  146             nd6_slowtimo, NULL);
  147 }
  148 
  149 void
  150 nd6_ifattach(ifp)
  151         struct ifnet *ifp;
  152 {
  153 
  154         /*
  155          * We have some arrays that should be indexed by if_index.
  156          * since if_index will grow dynamically, they should grow too.
  157          */
  158         if (nd_ifinfo == NULL || if_index >= nd_ifinfo_indexlim) {
  159                 size_t n;
  160                 caddr_t q;
  161 
  162                 while (if_index >= nd_ifinfo_indexlim)
  163                         nd_ifinfo_indexlim <<= 1;
  164 
  165                 /* grow nd_ifinfo */
  166                 n = nd_ifinfo_indexlim * sizeof(struct nd_ifinfo);
  167                 q = (caddr_t)malloc(n, M_IP6NDP, M_WAITOK);
  168                 bzero(q, n);
  169                 if (nd_ifinfo) {
  170                         bcopy((caddr_t)nd_ifinfo, q, n/2);
  171                         free((caddr_t)nd_ifinfo, M_IP6NDP);
  172                 }
  173                 nd_ifinfo = (struct nd_ifinfo *)q;
  174         }
  175 
  176 #define ND nd_ifinfo[ifp->if_index]
  177 
  178         /*
  179          * Don't initialize if called twice.
  180          * XXX: to detect this, we should choose a member that is never set
  181          * before initialization of the ND structure itself.  We formaly used
  182          * the linkmtu member, which was not suitable because it could be 
  183          * initialized via "ifconfig mtu".
  184          */
  185         if (ND.basereachable)
  186                 return;
  187 
  188         ND.linkmtu = ifnet_byindex(ifp->if_index)->if_mtu;
  189         ND.chlim = IPV6_DEFHLIM;
  190         ND.basereachable = REACHABLE_TIME;
  191         ND.reachable = ND_COMPUTE_RTIME(ND.basereachable);
  192         ND.retrans = RETRANS_TIMER;
  193         ND.receivedra = 0;
  194         ND.flags = ND6_IFF_PERFORMNUD;
  195         nd6_setmtu(ifp);
  196 #undef ND
  197 }
  198 
  199 /*
  200  * Reset ND level link MTU. This function is called when the physical MTU
  201  * changes, which means we might have to adjust the ND level MTU.
  202  */
  203 void
  204 nd6_setmtu(ifp)
  205         struct ifnet *ifp;
  206 {
  207 #define MIN(a,b) ((a) < (b) ? (a) : (b))
  208         struct nd_ifinfo *ndi = &nd_ifinfo[ifp->if_index];
  209         u_long oldmaxmtu = ndi->maxmtu;
  210         u_long oldlinkmtu = ndi->linkmtu;
  211 
  212         switch (ifp->if_type) {
  213         case IFT_ARCNET:        /* XXX MTU handling needs more work */
  214                 ndi->maxmtu = MIN(60480, ifp->if_mtu);
  215                 break;
  216         case IFT_ETHER:
  217                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
  218                 break;
  219         case IFT_FDDI:
  220                 ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu);
  221                 break;
  222         case IFT_ATM:
  223                 ndi->maxmtu = MIN(ATMMTU, ifp->if_mtu);
  224                 break;
  225         case IFT_IEEE1394:      /* XXX should be IEEE1394MTU(1500) */
  226                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
  227                 break;
  228 #ifdef IFT_IEEE80211
  229         case IFT_IEEE80211:     /* XXX should be IEEE80211MTU(1500) */
  230                 ndi->maxmtu = MIN(ETHERMTU, ifp->if_mtu);
  231                 break;
  232 #endif
  233         default:
  234                 ndi->maxmtu = ifp->if_mtu;
  235                 break;
  236         }
  237 
  238         if (oldmaxmtu != ndi->maxmtu) {
  239                 /*
  240                  * If the ND level MTU is not set yet, or if the maxmtu
  241                  * is reset to a smaller value than the ND level MTU,
  242                  * also reset the ND level MTU.
  243                  */
  244                 if (ndi->linkmtu == 0 ||
  245                     ndi->maxmtu < ndi->linkmtu) {
  246                         ndi->linkmtu = ndi->maxmtu;
  247                         /* also adjust in6_maxmtu if necessary. */
  248                         if (oldlinkmtu == 0) {
  249                                 /*
  250                                  * XXX: the case analysis is grotty, but
  251                                  * it is not efficient to call in6_setmaxmtu()
  252                                  * here when we are during the initialization
  253                                  * procedure.
  254                                  */
  255                                 if (in6_maxmtu < ndi->linkmtu)
  256                                         in6_maxmtu = ndi->linkmtu;
  257                         } else
  258                                 in6_setmaxmtu();
  259                 }
  260         }
  261 #undef MIN
  262 }
  263 
  264 void
  265 nd6_option_init(opt, icmp6len, ndopts)
  266         void *opt;
  267         int icmp6len;
  268         union nd_opts *ndopts;
  269 {
  270         bzero(ndopts, sizeof(*ndopts));
  271         ndopts->nd_opts_search = (struct nd_opt_hdr *)opt;
  272         ndopts->nd_opts_last
  273                 = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len);
  274 
  275         if (icmp6len == 0) {
  276                 ndopts->nd_opts_done = 1;
  277                 ndopts->nd_opts_search = NULL;
  278         }
  279 }
  280 
  281 /*
  282  * Take one ND option.
  283  */
  284 struct nd_opt_hdr *
  285 nd6_option(ndopts)
  286         union nd_opts *ndopts;
  287 {
  288         struct nd_opt_hdr *nd_opt;
  289         int olen;
  290 
  291         if (!ndopts)
  292                 panic("ndopts == NULL in nd6_option\n");
  293         if (!ndopts->nd_opts_last)
  294                 panic("uninitialized ndopts in nd6_option\n");
  295         if (!ndopts->nd_opts_search)
  296                 return NULL;
  297         if (ndopts->nd_opts_done)
  298                 return NULL;
  299 
  300         nd_opt = ndopts->nd_opts_search;
  301 
  302         /* make sure nd_opt_len is inside the buffer */
  303         if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) {
  304                 bzero(ndopts, sizeof(*ndopts));
  305                 return NULL;
  306         }
  307 
  308         olen = nd_opt->nd_opt_len << 3;
  309         if (olen == 0) {
  310                 /*
  311                  * Message validation requires that all included
  312                  * options have a length that is greater than zero.
  313                  */
  314                 bzero(ndopts, sizeof(*ndopts));
  315                 return NULL;
  316         }
  317 
  318         ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen);
  319         if (ndopts->nd_opts_search > ndopts->nd_opts_last) {
  320                 /* option overruns the end of buffer, invalid */
  321                 bzero(ndopts, sizeof(*ndopts));
  322                 return NULL;
  323         } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) {
  324                 /* reached the end of options chain */
  325                 ndopts->nd_opts_done = 1;
  326                 ndopts->nd_opts_search = NULL;
  327         }
  328         return nd_opt;
  329 }
  330 
  331 /*
  332  * Parse multiple ND options.
  333  * This function is much easier to use, for ND routines that do not need
  334  * multiple options of the same type.
  335  */
  336 int
  337 nd6_options(ndopts)
  338         union nd_opts *ndopts;
  339 {
  340         struct nd_opt_hdr *nd_opt;
  341         int i = 0;
  342 
  343         if (!ndopts)
  344                 panic("ndopts == NULL in nd6_options\n");
  345         if (!ndopts->nd_opts_last)
  346                 panic("uninitialized ndopts in nd6_options\n");
  347         if (!ndopts->nd_opts_search)
  348                 return 0;
  349 
  350         while (1) {
  351                 nd_opt = nd6_option(ndopts);
  352                 if (!nd_opt && !ndopts->nd_opts_last) {
  353                         /*
  354                          * Message validation requires that all included
  355                          * options have a length that is greater than zero.
  356                          */
  357                         icmp6stat.icp6s_nd_badopt++;
  358                         bzero(ndopts, sizeof(*ndopts));
  359                         return -1;
  360                 }
  361 
  362                 if (!nd_opt)
  363                         goto skip1;
  364 
  365                 switch (nd_opt->nd_opt_type) {
  366                 case ND_OPT_SOURCE_LINKADDR:
  367                 case ND_OPT_TARGET_LINKADDR:
  368                 case ND_OPT_MTU:
  369                 case ND_OPT_REDIRECTED_HEADER:
  370                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
  371                                 nd6log((LOG_INFO,
  372                                     "duplicated ND6 option found (type=%d)\n",
  373                                     nd_opt->nd_opt_type));
  374                                 /* XXX bark? */
  375                         } else {
  376                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
  377                                         = nd_opt;
  378                         }
  379                         break;
  380                 case ND_OPT_PREFIX_INFORMATION:
  381                         if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) {
  382                                 ndopts->nd_opt_array[nd_opt->nd_opt_type]
  383                                         = nd_opt;
  384                         }
  385                         ndopts->nd_opts_pi_end =
  386                                 (struct nd_opt_prefix_info *)nd_opt;
  387                         break;
  388                 default:
  389                         /*
  390                          * Unknown options must be silently ignored,
  391                          * to accomodate future extension to the protocol.
  392                          */
  393                         nd6log((LOG_DEBUG,
  394                             "nd6_options: unsupported option %d - "
  395                             "option ignored\n", nd_opt->nd_opt_type));
  396                 }
  397 
  398 skip1:
  399                 i++;
  400                 if (i > nd6_maxndopt) {
  401                         icmp6stat.icp6s_nd_toomanyopt++;
  402                         nd6log((LOG_INFO, "too many loop in nd opt\n"));
  403                         break;
  404                 }
  405 
  406                 if (ndopts->nd_opts_done)
  407                         break;
  408         }
  409 
  410         return 0;
  411 }
  412 
  413 /*
  414  * ND6 timer routine to expire default route list and prefix list
  415  */
  416 void
  417 nd6_timer(ignored_arg)
  418         void    *ignored_arg;
  419 {
  420         int s;
  421         struct llinfo_nd6 *ln;
  422         struct nd_defrouter *dr;
  423         struct nd_prefix *pr;
  424         struct ifnet *ifp;
  425         struct in6_ifaddr *ia6, *nia6;
  426         struct in6_addrlifetime *lt6;
  427         
  428         s = splnet();
  429         callout_reset(&nd6_timer_ch, nd6_prune * hz,
  430                       nd6_timer, NULL);
  431 
  432         ln = llinfo_nd6.ln_next;
  433         while (ln && ln != &llinfo_nd6) {
  434                 struct rtentry *rt;
  435                 struct sockaddr_in6 *dst;
  436                 struct llinfo_nd6 *next = ln->ln_next;
  437                 /* XXX: used for the DELAY case only: */
  438                 struct nd_ifinfo *ndi = NULL;
  439 
  440                 if ((rt = ln->ln_rt) == NULL) {
  441                         ln = next;
  442                         continue;
  443                 }
  444                 if ((ifp = rt->rt_ifp) == NULL) {
  445                         ln = next;
  446                         continue;
  447                 }
  448                 ndi = &nd_ifinfo[ifp->if_index];
  449                 dst = (struct sockaddr_in6 *)rt_key(rt);
  450 
  451                 if (ln->ln_expire > time_second) {
  452                         ln = next;
  453                         continue;
  454                 }
  455 
  456                 /* sanity check */
  457                 if (!rt)
  458                         panic("rt=0 in nd6_timer(ln=%p)\n", ln);
  459                 if (rt->rt_llinfo && (struct llinfo_nd6 *)rt->rt_llinfo != ln)
  460                         panic("rt_llinfo(%p) is not equal to ln(%p)\n",
  461                               rt->rt_llinfo, ln);
  462                 if (!dst)
  463                         panic("dst=0 in nd6_timer(ln=%p)\n", ln);
  464 
  465                 switch (ln->ln_state) {
  466                 case ND6_LLINFO_INCOMPLETE:
  467                         if (ln->ln_asked < nd6_mmaxtries) {
  468                                 ln->ln_asked++;
  469                                 ln->ln_expire = time_second +
  470                                         nd_ifinfo[ifp->if_index].retrans / 1000;
  471                                 nd6_ns_output(ifp, NULL, &dst->sin6_addr,
  472                                         ln, 0);
  473                         } else {
  474                                 struct mbuf *m = ln->ln_hold;
  475                                 if (m) {
  476                                         if (rt->rt_ifp) {
  477                                                 /*
  478                                                  * Fake rcvif to make ICMP error
  479                                                  * more helpful in diagnosing
  480                                                  * for the receiver.
  481                                                  * XXX: should we consider
  482                                                  * older rcvif?
  483                                                  */
  484                                                 m->m_pkthdr.rcvif = rt->rt_ifp;
  485                                         }
  486                                         icmp6_error(m, ICMP6_DST_UNREACH,
  487                                                     ICMP6_DST_UNREACH_ADDR, 0);
  488                                         ln->ln_hold = NULL;
  489                                 }
  490                                 next = nd6_free(rt);
  491                         }
  492                         break;
  493                 case ND6_LLINFO_REACHABLE:
  494                         if (ln->ln_expire) {
  495                                 ln->ln_state = ND6_LLINFO_STALE;
  496                                 ln->ln_expire = time_second + nd6_gctimer;
  497                         }
  498                         break;
  499 
  500                 case ND6_LLINFO_STALE:
  501                         /* Garbage Collection(RFC 2461 5.3) */
  502                         if (ln->ln_expire)
  503                                 next = nd6_free(rt);
  504                         break;
  505 
  506                 case ND6_LLINFO_DELAY:
  507                         if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) {
  508                                 /* We need NUD */
  509                                 ln->ln_asked = 1;
  510                                 ln->ln_state = ND6_LLINFO_PROBE;
  511                                 ln->ln_expire = time_second +
  512                                         ndi->retrans / 1000;
  513                                 nd6_ns_output(ifp, &dst->sin6_addr,
  514                                               &dst->sin6_addr,
  515                                               ln, 0);
  516                         } else {
  517                                 ln->ln_state = ND6_LLINFO_STALE; /* XXX */
  518                                 ln->ln_expire = time_second + nd6_gctimer;
  519                         }
  520                         break;
  521                 case ND6_LLINFO_PROBE:
  522                         if (ln->ln_asked < nd6_umaxtries) {
  523                                 ln->ln_asked++;
  524                                 ln->ln_expire = time_second +
  525                                         nd_ifinfo[ifp->if_index].retrans / 1000;
  526                                 nd6_ns_output(ifp, &dst->sin6_addr,
  527                                                &dst->sin6_addr, ln, 0);
  528                         } else {
  529                                 next = nd6_free(rt);
  530                         }
  531                         break;
  532                 }
  533                 ln = next;
  534         }
  535         
  536         /* expire default router list */
  537         dr = TAILQ_FIRST(&nd_defrouter);
  538         while (dr) {
  539                 if (dr->expire && dr->expire < time_second) {
  540                         struct nd_defrouter *t;
  541                         t = TAILQ_NEXT(dr, dr_entry);
  542                         defrtrlist_del(dr);
  543                         dr = t;
  544                 } else {
  545                         dr = TAILQ_NEXT(dr, dr_entry);
  546                 }
  547         }
  548 
  549         /*
  550          * expire interface addresses.
  551          * in the past the loop was inside prefix expiry processing.
  552          * However, from a stricter speci-confrmance standpoint, we should
  553          * rather separate address lifetimes and prefix lifetimes.
  554          */
  555   addrloop:
  556         for (ia6 = in6_ifaddr; ia6; ia6 = nia6) {
  557                 nia6 = ia6->ia_next;
  558                 /* check address lifetime */
  559                 lt6 = &ia6->ia6_lifetime;
  560                 if (IFA6_IS_INVALID(ia6)) {
  561                         int regen = 0;
  562 
  563                         /*
  564                          * If the expiring address is temporary, try
  565                          * regenerating a new one.  This would be useful when
  566                          * we suspended a laptop PC, then turned it on after a
  567                          * period that could invalidate all temporary
  568                          * addresses.  Although we may have to restart the
  569                          * loop (see below), it must be after purging the
  570                          * address.  Otherwise, we'd see an infinite loop of
  571                          * regeneration. 
  572                          */
  573                         if (ip6_use_tempaddr &&
  574                             (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
  575                                 if (regen_tmpaddr(ia6) == 0)
  576                                         regen = 1;
  577                         }
  578 
  579                         in6_purgeaddr(&ia6->ia_ifa);
  580 
  581                         if (regen)
  582                                 goto addrloop; /* XXX: see below */
  583                 }
  584                 if (IFA6_IS_DEPRECATED(ia6)) {
  585                         int oldflags = ia6->ia6_flags;
  586 
  587                         ia6->ia6_flags |= IN6_IFF_DEPRECATED;
  588 
  589                         /*
  590                          * If a temporary address has just become deprecated,
  591                          * regenerate a new one if possible.
  592                          */
  593                         if (ip6_use_tempaddr &&
  594                             (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
  595                             (oldflags & IN6_IFF_DEPRECATED) == 0) {
  596 
  597                                 if (regen_tmpaddr(ia6) == 0) {
  598                                         /*
  599                                          * A new temporary address is
  600                                          * generated.
  601                                          * XXX: this means the address chain
  602                                          * has changed while we are still in
  603                                          * the loop.  Although the change
  604                                          * would not cause disaster (because
  605                                          * it's not a deletion, but an
  606                                          * addition,) we'd rather restart the
  607                                          * loop just for safety.  Or does this 
  608                                          * significantly reduce performance??
  609                                          */
  610                                         goto addrloop;
  611                                 }
  612                         }
  613                 } else {
  614                         /*
  615                          * A new RA might have made a deprecated address
  616                          * preferred.
  617                          */
  618                         ia6->ia6_flags &= ~IN6_IFF_DEPRECATED;
  619                 }
  620         }
  621 
  622         /* expire prefix list */
  623         pr = nd_prefix.lh_first;
  624         while (pr) {
  625                 /*
  626                  * check prefix lifetime.
  627                  * since pltime is just for autoconf, pltime processing for
  628                  * prefix is not necessary.
  629                  */
  630                 if (pr->ndpr_expire && pr->ndpr_expire < time_second) {
  631                         struct nd_prefix *t;
  632                         t = pr->ndpr_next;
  633 
  634                         /*
  635                          * address expiration and prefix expiration are
  636                          * separate.  NEVER perform in6_purgeaddr here.
  637                          */
  638 
  639                         prelist_remove(pr);
  640                         pr = t;
  641                 } else
  642                         pr = pr->ndpr_next;
  643         }
  644         splx(s);
  645 }
  646 
  647 static int
  648 regen_tmpaddr(ia6)
  649         struct in6_ifaddr *ia6; /* deprecated/invalidated temporary address */
  650 {
  651         struct ifaddr *ifa;
  652         struct ifnet *ifp;
  653         struct in6_ifaddr *public_ifa6 = NULL;
  654 
  655         ifp = ia6->ia_ifa.ifa_ifp;
  656         for (ifa = ifp->if_addrlist.tqh_first; ifa;
  657              ifa = ifa->ifa_list.tqe_next)
  658         {
  659                 struct in6_ifaddr *it6;
  660 
  661                 if (ifa->ifa_addr->sa_family != AF_INET6)
  662                         continue;
  663 
  664                 it6 = (struct in6_ifaddr *)ifa;
  665 
  666                 /* ignore no autoconf addresses. */
  667                 if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0)
  668                         continue;
  669 
  670                 /* ignore autoconf addresses with different prefixes. */
  671                 if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr)
  672                         continue;
  673 
  674                 /*
  675                  * Now we are looking at an autoconf address with the same
  676                  * prefix as ours.  If the address is temporary and is still
  677                  * preferred, do not create another one.  It would be rare, but
  678                  * could happen, for example, when we resume a laptop PC after
  679                  * a long period.
  680                  */
  681                 if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
  682                     !IFA6_IS_DEPRECATED(it6)) {
  683                         public_ifa6 = NULL;
  684                         break;
  685                 }
  686 
  687                 /*
  688                  * This is a public autoconf address that has the same prefix
  689                  * as ours.  If it is preferred, keep it.  We can't break the
  690                  * loop here, because there may be a still-preferred temporary
  691                  * address with the prefix.
  692                  */
  693                 if (!IFA6_IS_DEPRECATED(it6))
  694                     public_ifa6 = it6;
  695         }
  696 
  697         if (public_ifa6 != NULL) {
  698                 int e;
  699 
  700                 if ((e = in6_tmpifadd(public_ifa6, 0)) != 0) {
  701                         log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
  702                             " tmp addr,errno=%d\n", e);
  703                         return(-1);
  704                 }
  705                 return(0);
  706         }
  707 
  708         return(-1);
  709 }
  710 
  711 /*
  712  * Nuke neighbor cache/prefix/default router management table, right before
  713  * ifp goes away.
  714  */
  715 void
  716 nd6_purge(ifp)
  717         struct ifnet *ifp;
  718 {
  719         struct llinfo_nd6 *ln, *nln;
  720         struct nd_defrouter *dr, *ndr, drany;
  721         struct nd_prefix *pr, *npr;
  722 
  723         /* Nuke default router list entries toward ifp */
  724         if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
  725                 /*
  726                  * The first entry of the list may be stored in
  727                  * the routing table, so we'll delete it later.
  728                  */
  729                 for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = ndr) {
  730                         ndr = TAILQ_NEXT(dr, dr_entry);
  731                         if (dr->ifp == ifp)
  732                                 defrtrlist_del(dr);
  733                 }
  734                 dr = TAILQ_FIRST(&nd_defrouter);
  735                 if (dr->ifp == ifp)
  736                         defrtrlist_del(dr);
  737         }
  738 
  739         /* Nuke prefix list entries toward ifp */
  740         for (pr = nd_prefix.lh_first; pr; pr = npr) {
  741                 npr = pr->ndpr_next;
  742                 if (pr->ndpr_ifp == ifp) {
  743                         /*
  744                          * Previously, pr->ndpr_addr is removed as well,
  745                          * but I strongly believe we don't have to do it.
  746                          * nd6_purge() is only called from in6_ifdetach(),
  747                          * which removes all the associated interface addresses
  748                          * by itself.
  749                          * (jinmei@kame.net 20010129)
  750                          */
  751                         prelist_remove(pr);
  752                 }
  753         }
  754 
  755         /* cancel default outgoing interface setting */
  756         if (nd6_defifindex == ifp->if_index)
  757                 nd6_setdefaultiface(0);
  758 
  759         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
  760                 /* refresh default router list */
  761                 bzero(&drany, sizeof(drany));
  762                 defrouter_delreq(&drany, 0);
  763                 defrouter_select();
  764         }
  765 
  766         /*
  767          * Nuke neighbor cache entries for the ifp.
  768          * Note that rt->rt_ifp may not be the same as ifp,
  769          * due to KAME goto ours hack.  See RTM_RESOLVE case in
  770          * nd6_rtrequest(), and ip6_input().
  771          */
  772         ln = llinfo_nd6.ln_next;
  773         while (ln && ln != &llinfo_nd6) {
  774                 struct rtentry *rt;
  775                 struct sockaddr_dl *sdl;
  776 
  777                 nln = ln->ln_next;
  778                 rt = ln->ln_rt;
  779                 if (rt && rt->rt_gateway &&
  780                     rt->rt_gateway->sa_family == AF_LINK) {
  781                         sdl = (struct sockaddr_dl *)rt->rt_gateway;
  782                         if (sdl->sdl_index == ifp->if_index)
  783                                 nln = nd6_free(rt);
  784                 }
  785                 ln = nln;
  786         }
  787 }
  788 
  789 struct rtentry *
  790 nd6_lookup(addr6, create, ifp)
  791         struct in6_addr *addr6;
  792         int create;
  793         struct ifnet *ifp;
  794 {
  795         struct rtentry *rt;
  796         struct sockaddr_in6 sin6;
  797 
  798         bzero(&sin6, sizeof(sin6));
  799         sin6.sin6_len = sizeof(struct sockaddr_in6);
  800         sin6.sin6_family = AF_INET6;
  801         sin6.sin6_addr = *addr6;
  802 #ifdef SCOPEDROUTING
  803         sin6.sin6_scope_id = in6_addr2scopeid(ifp, addr6);
  804 #endif
  805         rt = rtalloc1((struct sockaddr *)&sin6, create, 0UL);
  806         if (rt && (rt->rt_flags & RTF_LLINFO) == 0) {
  807                 /*
  808                  * This is the case for the default route.
  809                  * If we want to create a neighbor cache for the address, we
  810                  * should free the route for the destination and allocate an
  811                  * interface route.
  812                  */
  813                 if (create) {
  814                         RTFREE(rt);
  815                         rt = 0;
  816                 }
  817         }
  818         if (!rt) {
  819                 if (create && ifp) {
  820                         int e;
  821 
  822                         /*
  823                          * If no route is available and create is set,
  824                          * we allocate a host route for the destination
  825                          * and treat it like an interface route.
  826                          * This hack is necessary for a neighbor which can't
  827                          * be covered by our own prefix.
  828                          */
  829                         struct ifaddr *ifa =
  830                                 ifaof_ifpforaddr((struct sockaddr *)&sin6, ifp);
  831                         if (ifa == NULL)
  832                                 return(NULL);
  833 
  834                         /*
  835                          * Create a new route.  RTF_LLINFO is necessary
  836                          * to create a Neighbor Cache entry for the
  837                          * destination in nd6_rtrequest which will be
  838                          * called in rtrequest via ifa->ifa_rtrequest.
  839                          */
  840                         if ((e = rtrequest(RTM_ADD, (struct sockaddr *)&sin6,
  841                                            ifa->ifa_addr,
  842                                            (struct sockaddr *)&all1_sa,
  843                                            (ifa->ifa_flags |
  844                                             RTF_HOST | RTF_LLINFO) &
  845                                            ~RTF_CLONING,
  846                                            &rt)) != 0)
  847                                 log(LOG_ERR,
  848                                     "nd6_lookup: failed to add route for a "
  849                                     "neighbor(%s), errno=%d\n",
  850                                     ip6_sprintf(addr6), e);
  851                         if (rt == NULL)
  852                                 return(NULL);
  853                         if (rt->rt_llinfo) {
  854                                 struct llinfo_nd6 *ln =
  855                                         (struct llinfo_nd6 *)rt->rt_llinfo;
  856                                 ln->ln_state = ND6_LLINFO_NOSTATE;
  857                         }
  858                 } else
  859                         return(NULL);
  860         }
  861         rt->rt_refcnt--;
  862         /*
  863          * Validation for the entry.
  864          * Note that the check for rt_llinfo is necessary because a cloned
  865          * route from a parent route that has the L flag (e.g. the default
  866          * route to a p2p interface) may have the flag, too, while the
  867          * destination is not actually a neighbor.
  868          * XXX: we can't use rt->rt_ifp to check for the interface, since
  869          *      it might be the loopback interface if the entry is for our
  870          *      own address on a non-loopback interface. Instead, we should
  871          *      use rt->rt_ifa->ifa_ifp, which would specify the REAL
  872          *      interface.
  873          */
  874         if ((rt->rt_flags & RTF_GATEWAY) || (rt->rt_flags & RTF_LLINFO) == 0 ||
  875             rt->rt_gateway->sa_family != AF_LINK || rt->rt_llinfo == NULL ||
  876             (ifp && rt->rt_ifa->ifa_ifp != ifp)) {
  877                 if (create) {
  878                         log(LOG_DEBUG, "nd6_lookup: failed to lookup %s (if = %s)\n",
  879                             ip6_sprintf(addr6), ifp ? if_name(ifp) : "unspec");
  880                         /* xxx more logs... kazu */
  881                 }
  882                 return(NULL);
  883         }
  884         return(rt);
  885 }
  886 
  887 /*
  888  * Detect if a given IPv6 address identifies a neighbor on a given link.
  889  * XXX: should take care of the destination of a p2p link?
  890  */
  891 int
  892 nd6_is_addr_neighbor(addr, ifp)
  893         struct sockaddr_in6 *addr;
  894         struct ifnet *ifp;
  895 {
  896         struct ifaddr *ifa;
  897         int i;
  898 
  899 #define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
  900 #define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
  901 
  902         /*
  903          * A link-local address is always a neighbor.
  904          * XXX: we should use the sin6_scope_id field rather than the embedded
  905          * interface index.
  906          */
  907         if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
  908             ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
  909                 return(1);
  910 
  911         /*
  912          * If the address matches one of our addresses,
  913          * it should be a neighbor.
  914          */
  915         for (ifa = ifp->if_addrlist.tqh_first;
  916              ifa;
  917              ifa = ifa->ifa_list.tqe_next)
  918         {
  919                 if (ifa->ifa_addr->sa_family != AF_INET6)
  920                         next: continue;
  921 
  922                 for (i = 0; i < 4; i++) {
  923                         if ((IFADDR6(ifa).s6_addr32[i] ^
  924                              addr->sin6_addr.s6_addr32[i]) &
  925                             IFMASK6(ifa).s6_addr32[i])
  926                                 goto next;
  927                 }
  928                 return(1);
  929         }
  930 
  931         /*
  932          * Even if the address matches none of our addresses, it might be
  933          * in the neighbor cache.
  934          */
  935         if (nd6_lookup(&addr->sin6_addr, 0, ifp) != NULL)
  936                 return(1);
  937 
  938         return(0);
  939 #undef IFADDR6
  940 #undef IFMASK6
  941 }
  942 
  943 /*
  944  * Free an nd6 llinfo entry.
  945  */
  946 struct llinfo_nd6 *
  947 nd6_free(rt)
  948         struct rtentry *rt;
  949 {
  950         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo, *next;
  951         struct in6_addr in6 = ((struct sockaddr_in6 *)rt_key(rt))->sin6_addr;
  952         struct nd_defrouter *dr;
  953 
  954         /*
  955          * we used to have pfctlinput(PRC_HOSTDEAD) here. 
  956          * even though it is not harmful, it was not really necessary.
  957          */
  958 
  959         if (!ip6_forwarding && ip6_accept_rtadv) { /* XXX: too restrictive? */
  960                 int s;
  961                 s = splnet();
  962                 dr = defrouter_lookup(&((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
  963                                       rt->rt_ifp);
  964 
  965                 if (ln->ln_router || dr) {
  966                         /*
  967                          * rt6_flush must be called whether or not the neighbor
  968                          * is in the Default Router List.
  969                          * See a corresponding comment in nd6_na_input().
  970                          */
  971                         rt6_flush(&in6, rt->rt_ifp);
  972                 }
  973 
  974                 if (dr) {
  975                         /*
  976                          * Unreachablity of a router might affect the default
  977                          * router selection and on-link detection of advertised
  978                          * prefixes.
  979                          */
  980 
  981                         /*
  982                          * Temporarily fake the state to choose a new default
  983                          * router and to perform on-link determination of
  984                          * prefixes correctly.
  985                          * Below the state will be set correctly,
  986                          * or the entry itself will be deleted.
  987                          */
  988                         ln->ln_state = ND6_LLINFO_INCOMPLETE;
  989 
  990                         /*
  991                          * Since defrouter_select() does not affect the
  992                          * on-link determination and MIP6 needs the check
  993                          * before the default router selection, we perform
  994                          * the check now.
  995                          */
  996                         pfxlist_onlink_check();
  997 
  998                         if (dr == TAILQ_FIRST(&nd_defrouter)) {
  999                                 /*
 1000                                  * It is used as the current default router,
 1001                                  * so we have to move it to the end of the
 1002                                  * list and choose a new one.
 1003                                  * XXX: it is not very efficient if this is
 1004                                  *      the only router.
 1005                                  */
 1006                                 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
 1007                                 TAILQ_INSERT_TAIL(&nd_defrouter, dr, dr_entry);
 1008 
 1009                                 defrouter_select();
 1010                         }
 1011                 }
 1012                 splx(s);
 1013         }
 1014 
 1015         /*
 1016          * Before deleting the entry, remember the next entry as the
 1017          * return value.  We need this because pfxlist_onlink_check() above
 1018          * might have freed other entries (particularly the old next entry) as
 1019          * a side effect (XXX).
 1020          */
 1021         next = ln->ln_next;
 1022 
 1023         /*
 1024          * Detach the route from the routing tree and the list of neighbor
 1025          * caches, and disable the route entry not to be used in already
 1026          * cached routes.
 1027          */
 1028         rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0,
 1029                   rt_mask(rt), 0, (struct rtentry **)0);
 1030 
 1031         return(next);
 1032 }
 1033 
 1034 /*
 1035  * Upper-layer reachability hint for Neighbor Unreachability Detection.
 1036  *
 1037  * XXX cost-effective metods?
 1038  */
 1039 void
 1040 nd6_nud_hint(rt, dst6, force)
 1041         struct rtentry *rt;
 1042         struct in6_addr *dst6;
 1043         int force;
 1044 {
 1045         struct llinfo_nd6 *ln;
 1046 
 1047         /*
 1048          * If the caller specified "rt", use that.  Otherwise, resolve the
 1049          * routing table by supplied "dst6".
 1050          */
 1051         if (!rt) {
 1052                 if (!dst6)
 1053                         return;
 1054                 if (!(rt = nd6_lookup(dst6, 0, NULL)))
 1055                         return;
 1056         }
 1057 
 1058         if ((rt->rt_flags & RTF_GATEWAY) != 0 ||
 1059             (rt->rt_flags & RTF_LLINFO) == 0 ||
 1060             !rt->rt_llinfo || !rt->rt_gateway ||
 1061             rt->rt_gateway->sa_family != AF_LINK) {
 1062                 /* This is not a host route. */
 1063                 return;
 1064         }
 1065 
 1066         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1067         if (ln->ln_state < ND6_LLINFO_REACHABLE)
 1068                 return;
 1069 
 1070         /*
 1071          * if we get upper-layer reachability confirmation many times,
 1072          * it is possible we have false information.
 1073          */
 1074         if (!force) {
 1075                 ln->ln_byhint++;
 1076                 if (ln->ln_byhint > nd6_maxnudhint)
 1077                         return;
 1078         }
 1079 
 1080         ln->ln_state = ND6_LLINFO_REACHABLE;
 1081         if (ln->ln_expire)
 1082                 ln->ln_expire = time_second +
 1083                         nd_ifinfo[rt->rt_ifp->if_index].reachable;
 1084 }
 1085 
 1086 void
 1087 nd6_rtrequest(req, rt, info)
 1088         int     req;
 1089         struct rtentry *rt;
 1090         struct rt_addrinfo *info; /* xxx unused */
 1091 {
 1092         struct sockaddr *gate = rt->rt_gateway;
 1093         struct llinfo_nd6 *ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1094         static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
 1095         struct ifnet *ifp = rt->rt_ifp;
 1096         struct ifaddr *ifa;
 1097 
 1098         if ((rt->rt_flags & RTF_GATEWAY))
 1099                 return;
 1100 
 1101         if (nd6_need_cache(ifp) == 0 && (rt->rt_flags & RTF_HOST) == 0) {
 1102                 /*
 1103                  * This is probably an interface direct route for a link
 1104                  * which does not need neighbor caches (e.g. fe80::%lo0/64).
 1105                  * We do not need special treatment below for such a route.
 1106                  * Moreover, the RTF_LLINFO flag which would be set below
 1107                  * would annoy the ndp(8) command.
 1108                  */
 1109                 return;
 1110         }
 1111 
 1112         if (req == RTM_RESOLVE &&
 1113             (nd6_need_cache(ifp) == 0 || /* stf case */
 1114              !nd6_is_addr_neighbor((struct sockaddr_in6 *)rt_key(rt), ifp))) {
 1115                 /*
 1116                  * FreeBSD and BSD/OS often make a cloned host route based
 1117                  * on a less-specific route (e.g. the default route).
 1118                  * If the less specific route does not have a "gateway"
 1119                  * (this is the case when the route just goes to a p2p or an
 1120                  * stf interface), we'll mistakenly make a neighbor cache for
 1121                  * the host route, and will see strange neighbor solicitation
 1122                  * for the corresponding destination.  In order to avoid the
 1123                  * confusion, we check if the destination of the route is
 1124                  * a neighbor in terms of neighbor discovery, and stop the
 1125                  * process if not.  Additionally, we remove the LLINFO flag
 1126                  * so that ndp(8) will not try to get the neighbor information
 1127                  * of the destination.
 1128                  */
 1129                 rt->rt_flags &= ~RTF_LLINFO;
 1130                 return;
 1131         }
 1132 
 1133         switch (req) {
 1134         case RTM_ADD:
 1135                 /*
 1136                  * There is no backward compatibility :)
 1137                  *
 1138                  * if ((rt->rt_flags & RTF_HOST) == 0 &&
 1139                  *     SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
 1140                  *         rt->rt_flags |= RTF_CLONING;
 1141                  */
 1142                 if (rt->rt_flags & (RTF_CLONING | RTF_LLINFO)) {
 1143                         /*
 1144                          * Case 1: This route should come from
 1145                          * a route to interface.  RTF_LLINFO flag is set
 1146                          * for a host route whose destination should be
 1147                          * treated as on-link.
 1148                          */
 1149                         rt_setgate(rt, rt_key(rt),
 1150                                    (struct sockaddr *)&null_sdl);
 1151                         gate = rt->rt_gateway;
 1152                         SDL(gate)->sdl_type = ifp->if_type;
 1153                         SDL(gate)->sdl_index = ifp->if_index;
 1154                         if (ln)
 1155                                 ln->ln_expire = time_second;
 1156 #if 1
 1157                         if (ln && ln->ln_expire == 0) {
 1158                                 /* kludge for desktops */
 1159 #if 0
 1160                                 printf("nd6_rtequest: time.tv_sec is zero; "
 1161                                        "treat it as 1\n");
 1162 #endif
 1163                                 ln->ln_expire = 1;
 1164                         }
 1165 #endif
 1166                         if ((rt->rt_flags & RTF_CLONING))
 1167                                 break;
 1168                 }
 1169                 /*
 1170                  * In IPv4 code, we try to annonuce new RTF_ANNOUNCE entry here.
 1171                  * We don't do that here since llinfo is not ready yet.
 1172                  *
 1173                  * There are also couple of other things to be discussed:
 1174                  * - unsolicited NA code needs improvement beforehand
 1175                  * - RFC2461 says we MAY send multicast unsolicited NA
 1176                  *   (7.2.6 paragraph 4), however, it also says that we
 1177                  *   SHOULD provide a mechanism to prevent multicast NA storm.
 1178                  *   we don't have anything like it right now.
 1179                  *   note that the mechanism needs a mutual agreement
 1180                  *   between proxies, which means that we need to implement
 1181                  *   a new protocol, or a new kludge.
 1182                  * - from RFC2461 6.2.4, host MUST NOT send an unsolicited NA.
 1183                  *   we need to check ip6forwarding before sending it.
 1184                  *   (or should we allow proxy ND configuration only for
 1185                  *   routers?  there's no mention about proxy ND from hosts)
 1186                  */
 1187 #if 0
 1188                 /* XXX it does not work */
 1189                 if (rt->rt_flags & RTF_ANNOUNCE)
 1190                         nd6_na_output(ifp,
 1191                               &SIN6(rt_key(rt))->sin6_addr,
 1192                               &SIN6(rt_key(rt))->sin6_addr,
 1193                               ip6_forwarding ? ND_NA_FLAG_ROUTER : 0,
 1194                               1, NULL);
 1195 #endif
 1196                 /* FALLTHROUGH */
 1197         case RTM_RESOLVE:
 1198                 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) {
 1199                         /*
 1200                          * Address resolution isn't necessary for a point to
 1201                          * point link, so we can skip this test for a p2p link.
 1202                          */
 1203                         if (gate->sa_family != AF_LINK ||
 1204                             gate->sa_len < sizeof(null_sdl)) {
 1205                                 log(LOG_DEBUG,
 1206                                     "nd6_rtrequest: bad gateway value: %s\n",
 1207                                     if_name(ifp));
 1208                                 break;
 1209                         }
 1210                         SDL(gate)->sdl_type = ifp->if_type;
 1211                         SDL(gate)->sdl_index = ifp->if_index;
 1212                 }
 1213                 if (ln != NULL)
 1214                         break;  /* This happens on a route change */
 1215                 /*
 1216                  * Case 2: This route may come from cloning, or a manual route
 1217                  * add with a LL address.
 1218                  */
 1219                 R_Malloc(ln, struct llinfo_nd6 *, sizeof(*ln));
 1220                 rt->rt_llinfo = (caddr_t)ln;
 1221                 if (!ln) {
 1222                         log(LOG_DEBUG, "nd6_rtrequest: malloc failed\n");
 1223                         break;
 1224                 }
 1225                 nd6_inuse++;
 1226                 nd6_allocated++;
 1227                 Bzero(ln, sizeof(*ln));
 1228                 ln->ln_rt = rt;
 1229                 /* this is required for "ndp" command. - shin */
 1230                 if (req == RTM_ADD) {
 1231                         /*
 1232                          * gate should have some valid AF_LINK entry,
 1233                          * and ln->ln_expire should have some lifetime
 1234                          * which is specified by ndp command.
 1235                          */
 1236                         ln->ln_state = ND6_LLINFO_REACHABLE;
 1237                         ln->ln_byhint = 0;
 1238                 } else {
 1239                         /*
 1240                          * When req == RTM_RESOLVE, rt is created and
 1241                          * initialized in rtrequest(), so rt_expire is 0.
 1242                          */
 1243                         ln->ln_state = ND6_LLINFO_NOSTATE;
 1244                         ln->ln_expire = time_second;
 1245                 }
 1246                 rt->rt_flags |= RTF_LLINFO;
 1247                 ln->ln_next = llinfo_nd6.ln_next;
 1248                 llinfo_nd6.ln_next = ln;
 1249                 ln->ln_prev = &llinfo_nd6;
 1250                 ln->ln_next->ln_prev = ln;
 1251 
 1252                 /*
 1253                  * check if rt_key(rt) is one of my address assigned
 1254                  * to the interface.
 1255                  */
 1256                 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(rt->rt_ifp,
 1257                                           &SIN6(rt_key(rt))->sin6_addr);
 1258                 if (ifa) {
 1259                         caddr_t macp = nd6_ifptomac(ifp);
 1260                         ln->ln_expire = 0;
 1261                         ln->ln_state = ND6_LLINFO_REACHABLE;
 1262                         ln->ln_byhint = 0;
 1263                         if (macp) {
 1264                                 Bcopy(macp, LLADDR(SDL(gate)), ifp->if_addrlen);
 1265                                 SDL(gate)->sdl_alen = ifp->if_addrlen;
 1266                         }
 1267                         if (nd6_useloopback) {
 1268                                 rt->rt_ifp = &loif[0];  /* XXX */
 1269                                 /*
 1270                                  * Make sure rt_ifa be equal to the ifaddr
 1271                                  * corresponding to the address.
 1272                                  * We need this because when we refer
 1273                                  * rt_ifa->ia6_flags in ip6_input, we assume
 1274                                  * that the rt_ifa points to the address instead
 1275                                  * of the loopback address.
 1276                                  */
 1277                                 if (ifa != rt->rt_ifa) {
 1278                                         IFAFREE(rt->rt_ifa);
 1279                                         IFAREF(ifa);
 1280                                         rt->rt_ifa = ifa;
 1281                                 }
 1282                         }
 1283                 } else if (rt->rt_flags & RTF_ANNOUNCE) {
 1284                         ln->ln_expire = 0;
 1285                         ln->ln_state = ND6_LLINFO_REACHABLE;
 1286                         ln->ln_byhint = 0;
 1287 
 1288                         /* join solicited node multicast for proxy ND */
 1289                         if (ifp->if_flags & IFF_MULTICAST) {
 1290                                 struct in6_addr llsol;
 1291                                 int error;
 1292 
 1293                                 llsol = SIN6(rt_key(rt))->sin6_addr;
 1294                                 llsol.s6_addr16[0] = htons(0xff02);
 1295                                 llsol.s6_addr16[1] = htons(ifp->if_index);
 1296                                 llsol.s6_addr32[1] = 0;
 1297                                 llsol.s6_addr32[2] = htonl(1);
 1298                                 llsol.s6_addr8[12] = 0xff;
 1299 
 1300                                 if (!in6_addmulti(&llsol, ifp, &error)) {
 1301                                         nd6log((LOG_ERR, "%s: failed to join "
 1302                                             "%s (errno=%d)\n", if_name(ifp),
 1303                                             ip6_sprintf(&llsol), error));
 1304                                 }
 1305                         }
 1306                 }
 1307                 break;
 1308 
 1309         case RTM_DELETE:
 1310                 if (!ln)
 1311                         break;
 1312                 /* leave from solicited node multicast for proxy ND */
 1313                 if ((rt->rt_flags & RTF_ANNOUNCE) != 0 &&
 1314                     (ifp->if_flags & IFF_MULTICAST) != 0) {
 1315                         struct in6_addr llsol;
 1316                         struct in6_multi *in6m;
 1317 
 1318                         llsol = SIN6(rt_key(rt))->sin6_addr;
 1319                         llsol.s6_addr16[0] = htons(0xff02);
 1320                         llsol.s6_addr16[1] = htons(ifp->if_index);
 1321                         llsol.s6_addr32[1] = 0;
 1322                         llsol.s6_addr32[2] = htonl(1);
 1323                         llsol.s6_addr8[12] = 0xff;
 1324 
 1325                         IN6_LOOKUP_MULTI(llsol, ifp, in6m);
 1326                         if (in6m)
 1327                                 in6_delmulti(in6m);
 1328                 }
 1329                 nd6_inuse--;
 1330                 ln->ln_next->ln_prev = ln->ln_prev;
 1331                 ln->ln_prev->ln_next = ln->ln_next;
 1332                 ln->ln_prev = NULL;
 1333                 rt->rt_llinfo = 0;
 1334                 rt->rt_flags &= ~RTF_LLINFO;
 1335                 if (ln->ln_hold)
 1336                         m_freem(ln->ln_hold);
 1337                 Free((caddr_t)ln);
 1338         }
 1339 }
 1340 
 1341 int
 1342 nd6_ioctl(cmd, data, ifp)
 1343         u_long cmd;
 1344         caddr_t data;
 1345         struct ifnet *ifp;
 1346 {
 1347         struct in6_drlist *drl = (struct in6_drlist *)data;
 1348         struct in6_prlist *prl = (struct in6_prlist *)data;
 1349         struct in6_ndireq *ndi = (struct in6_ndireq *)data;
 1350         struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data;
 1351         struct in6_ndifreq *ndif = (struct in6_ndifreq *)data;
 1352         struct nd_defrouter *dr, any;
 1353         struct nd_prefix *pr;
 1354         struct rtentry *rt;
 1355         int i = 0, error = 0;
 1356         int s;
 1357 
 1358         switch (cmd) {
 1359         case SIOCGDRLST_IN6:
 1360                 /*
 1361                  * obsolete API, use sysctl under net.inet6.icmp6
 1362                  */
 1363                 bzero(drl, sizeof(*drl));
 1364                 s = splnet();
 1365                 dr = TAILQ_FIRST(&nd_defrouter);
 1366                 while (dr && i < DRLSTSIZ) {
 1367                         drl->defrouter[i].rtaddr = dr->rtaddr;
 1368                         if (IN6_IS_ADDR_LINKLOCAL(&drl->defrouter[i].rtaddr)) {
 1369                                 /* XXX: need to this hack for KAME stack */
 1370                                 drl->defrouter[i].rtaddr.s6_addr16[1] = 0;
 1371                         } else
 1372                                 log(LOG_ERR,
 1373                                     "default router list contains a "
 1374                                     "non-linklocal address(%s)\n",
 1375                                     ip6_sprintf(&drl->defrouter[i].rtaddr));
 1376 
 1377                         drl->defrouter[i].flags = dr->flags;
 1378                         drl->defrouter[i].rtlifetime = dr->rtlifetime;
 1379                         drl->defrouter[i].expire = dr->expire;
 1380                         drl->defrouter[i].if_index = dr->ifp->if_index;
 1381                         i++;
 1382                         dr = TAILQ_NEXT(dr, dr_entry);
 1383                 }
 1384                 splx(s);
 1385                 break;
 1386         case SIOCGPRLST_IN6:
 1387                 /*
 1388                  * obsolete API, use sysctl under net.inet6.icmp6
 1389                  */
 1390                 /*
 1391                  * XXX meaning of fields, especialy "raflags", is very
 1392                  * differnet between RA prefix list and RR/static prefix list.
 1393                  * how about separating ioctls into two?
 1394                  */
 1395                 bzero(prl, sizeof(*prl));
 1396                 s = splnet();
 1397                 pr = nd_prefix.lh_first;
 1398                 while (pr && i < PRLSTSIZ) {
 1399                         struct nd_pfxrouter *pfr;
 1400                         int j;
 1401 
 1402                         (void)in6_embedscope(&prl->prefix[i].prefix,
 1403                             &pr->ndpr_prefix, NULL, NULL);
 1404                         prl->prefix[i].raflags = pr->ndpr_raf;
 1405                         prl->prefix[i].prefixlen = pr->ndpr_plen;
 1406                         prl->prefix[i].vltime = pr->ndpr_vltime;
 1407                         prl->prefix[i].pltime = pr->ndpr_pltime;
 1408                         prl->prefix[i].if_index = pr->ndpr_ifp->if_index;
 1409                         prl->prefix[i].expire = pr->ndpr_expire;
 1410 
 1411                         pfr = pr->ndpr_advrtrs.lh_first;
 1412                         j = 0;
 1413                         while (pfr) {
 1414                                 if (j < DRLSTSIZ) {
 1415 #define RTRADDR prl->prefix[i].advrtr[j]
 1416                                         RTRADDR = pfr->router->rtaddr;
 1417                                         if (IN6_IS_ADDR_LINKLOCAL(&RTRADDR)) {
 1418                                                 /* XXX: hack for KAME */
 1419                                                 RTRADDR.s6_addr16[1] = 0;
 1420                                         } else
 1421                                                 log(LOG_ERR,
 1422                                                     "a router(%s) advertises "
 1423                                                     "a prefix with "
 1424                                                     "non-link local address\n",
 1425                                                     ip6_sprintf(&RTRADDR));
 1426 #undef RTRADDR
 1427                                 }
 1428                                 j++;
 1429                                 pfr = pfr->pfr_next;
 1430                         }
 1431                         prl->prefix[i].advrtrs = j;
 1432                         prl->prefix[i].origin = PR_ORIG_RA;
 1433 
 1434                         i++;
 1435                         pr = pr->ndpr_next;
 1436                 }
 1437               {
 1438                 struct rr_prefix *rpp;
 1439 
 1440                 for (rpp = LIST_FIRST(&rr_prefix); rpp;
 1441                      rpp = LIST_NEXT(rpp, rp_entry)) {
 1442                         if (i >= PRLSTSIZ)
 1443                                 break;
 1444                         (void)in6_embedscope(&prl->prefix[i].prefix,
 1445                             &pr->ndpr_prefix, NULL, NULL);
 1446                         prl->prefix[i].raflags = rpp->rp_raf;
 1447                         prl->prefix[i].prefixlen = rpp->rp_plen;
 1448                         prl->prefix[i].vltime = rpp->rp_vltime;
 1449                         prl->prefix[i].pltime = rpp->rp_pltime;
 1450                         prl->prefix[i].if_index = rpp->rp_ifp->if_index;
 1451                         prl->prefix[i].expire = rpp->rp_expire;
 1452                         prl->prefix[i].advrtrs = 0;
 1453                         prl->prefix[i].origin = rpp->rp_origin;
 1454                         i++;
 1455                 }
 1456               }
 1457                 splx(s);
 1458 
 1459                 break;
 1460         case OSIOCGIFINFO_IN6:
 1461                 if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
 1462                         error = EINVAL;
 1463                         break;
 1464                 }
 1465                 ndi->ndi.linkmtu = nd_ifinfo[ifp->if_index].linkmtu;
 1466                 ndi->ndi.maxmtu = nd_ifinfo[ifp->if_index].maxmtu;
 1467                 ndi->ndi.basereachable =
 1468                     nd_ifinfo[ifp->if_index].basereachable;
 1469                 ndi->ndi.reachable = nd_ifinfo[ifp->if_index].reachable;
 1470                 ndi->ndi.retrans = nd_ifinfo[ifp->if_index].retrans;
 1471                 ndi->ndi.flags = nd_ifinfo[ifp->if_index].flags;
 1472                 ndi->ndi.recalctm = nd_ifinfo[ifp->if_index].recalctm;
 1473                 ndi->ndi.chlim = nd_ifinfo[ifp->if_index].chlim;
 1474                 ndi->ndi.receivedra = nd_ifinfo[ifp->if_index].receivedra;
 1475                 break;
 1476         case SIOCGIFINFO_IN6:
 1477                 if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
 1478                         error = EINVAL;
 1479                         break;
 1480                 }
 1481                 ndi->ndi = nd_ifinfo[ifp->if_index];
 1482                 break;
 1483         case SIOCSIFINFO_FLAGS:
 1484                 /* XXX: almost all other fields of ndi->ndi is unused */
 1485                 if (!nd_ifinfo || i >= nd_ifinfo_indexlim) {
 1486                         error = EINVAL;
 1487                         break;
 1488                 }
 1489                 nd_ifinfo[ifp->if_index].flags = ndi->ndi.flags;
 1490                 break;
 1491         case SIOCSNDFLUSH_IN6:  /* XXX: the ioctl name is confusing... */
 1492                 /* flush default router list */
 1493                 /*
 1494                  * xxx sumikawa: should not delete route if default
 1495                  * route equals to the top of default router list
 1496                  */
 1497                 bzero(&any, sizeof(any));
 1498                 defrouter_delreq(&any, 0);
 1499                 defrouter_select();
 1500                 /* xxx sumikawa: flush prefix list */
 1501                 break;
 1502         case SIOCSPFXFLUSH_IN6:
 1503             {
 1504                 /* flush all the prefix advertised by routers */
 1505                 struct nd_prefix *pr, *next;
 1506 
 1507                 s = splnet();
 1508                 for (pr = nd_prefix.lh_first; pr; pr = next) {
 1509                         struct in6_ifaddr *ia, *ia_next;
 1510 
 1511                         next = pr->ndpr_next;
 1512 
 1513                         if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
 1514                                 continue; /* XXX */
 1515 
 1516                         /* do we really have to remove addresses as well? */
 1517                         for (ia = in6_ifaddr; ia; ia = ia_next) {
 1518                                 /* ia might be removed.  keep the next ptr. */
 1519                                 ia_next = ia->ia_next;
 1520 
 1521                                 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0)
 1522                                         continue;
 1523 
 1524                                 if (ia->ia6_ndpr == pr)
 1525                                         in6_purgeaddr(&ia->ia_ifa);
 1526                         }
 1527                         prelist_remove(pr);
 1528                 }
 1529                 splx(s);
 1530                 break;
 1531             }
 1532         case SIOCSRTRFLUSH_IN6:
 1533             {
 1534                 /* flush all the default routers */
 1535                 struct nd_defrouter *dr, *next;
 1536 
 1537                 s = splnet();
 1538                 if ((dr = TAILQ_FIRST(&nd_defrouter)) != NULL) {
 1539                         /*
 1540                          * The first entry of the list may be stored in
 1541                          * the routing table, so we'll delete it later.
 1542                          */
 1543                         for (dr = TAILQ_NEXT(dr, dr_entry); dr; dr = next) {
 1544                                 next = TAILQ_NEXT(dr, dr_entry);
 1545                                 defrtrlist_del(dr);
 1546                         }
 1547                         defrtrlist_del(TAILQ_FIRST(&nd_defrouter));
 1548                 }
 1549                 splx(s);
 1550                 break;
 1551             }
 1552         case SIOCGNBRINFO_IN6:
 1553             {
 1554                 struct llinfo_nd6 *ln;
 1555                 struct in6_addr nb_addr = nbi->addr; /* make local for safety */
 1556 
 1557                 /*
 1558                  * XXX: KAME specific hack for scoped addresses
 1559                  *      XXXX: for other scopes than link-local?
 1560                  */
 1561                 if (IN6_IS_ADDR_LINKLOCAL(&nbi->addr) ||
 1562                     IN6_IS_ADDR_MC_LINKLOCAL(&nbi->addr)) {
 1563                         u_int16_t *idp = (u_int16_t *)&nb_addr.s6_addr[2];
 1564 
 1565                         if (*idp == 0)
 1566                                 *idp = htons(ifp->if_index);
 1567                 }
 1568 
 1569                 s = splnet();
 1570                 if ((rt = nd6_lookup(&nb_addr, 0, ifp)) == NULL) {
 1571                         error = EINVAL;
 1572                         splx(s);
 1573                         break;
 1574                 }
 1575                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1576                 nbi->state = ln->ln_state;
 1577                 nbi->asked = ln->ln_asked;
 1578                 nbi->isrouter = ln->ln_router;
 1579                 nbi->expire = ln->ln_expire;
 1580                 splx(s);
 1581                 
 1582                 break;
 1583             }
 1584         case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
 1585                 ndif->ifindex = nd6_defifindex;
 1586                 break;
 1587         case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */
 1588                 return(nd6_setdefaultiface(ndif->ifindex));
 1589                 break;
 1590         }
 1591         return(error);
 1592 }
 1593 
 1594 /*
 1595  * Create neighbor cache entry and cache link-layer address,
 1596  * on reception of inbound ND6 packets. (RS/RA/NS/redirect)
 1597  */
 1598 struct rtentry *
 1599 nd6_cache_lladdr(ifp, from, lladdr, lladdrlen, type, code)
 1600         struct ifnet *ifp;
 1601         struct in6_addr *from;
 1602         char *lladdr;
 1603         int lladdrlen;
 1604         int type;       /* ICMP6 type */
 1605         int code;       /* type dependent information */
 1606 {
 1607         struct rtentry *rt = NULL;
 1608         struct llinfo_nd6 *ln = NULL;
 1609         int is_newentry;
 1610         struct sockaddr_dl *sdl = NULL;
 1611         int do_update;
 1612         int olladdr;
 1613         int llchange;
 1614         int newstate = 0;
 1615 
 1616         if (!ifp)
 1617                 panic("ifp == NULL in nd6_cache_lladdr");
 1618         if (!from)
 1619                 panic("from == NULL in nd6_cache_lladdr");
 1620 
 1621         /* nothing must be updated for unspecified address */
 1622         if (IN6_IS_ADDR_UNSPECIFIED(from))
 1623                 return NULL;
 1624 
 1625         /*
 1626          * Validation about ifp->if_addrlen and lladdrlen must be done in
 1627          * the caller.
 1628          *
 1629          * XXX If the link does not have link-layer adderss, what should
 1630          * we do? (ifp->if_addrlen == 0)
 1631          * Spec says nothing in sections for RA, RS and NA.  There's small
 1632          * description on it in NS section (RFC 2461 7.2.3).
 1633          */
 1634 
 1635         rt = nd6_lookup(from, 0, ifp);
 1636         if (!rt) {
 1637 #if 0
 1638                 /* nothing must be done if there's no lladdr */
 1639                 if (!lladdr || !lladdrlen)
 1640                         return NULL;
 1641 #endif
 1642 
 1643                 rt = nd6_lookup(from, 1, ifp);
 1644                 is_newentry = 1;
 1645         } else {
 1646                 /* do nothing if static ndp is set */
 1647                 if (rt->rt_flags & RTF_STATIC)
 1648                         return NULL;
 1649                 is_newentry = 0;
 1650         }
 1651 
 1652         if (!rt)
 1653                 return NULL;
 1654         if ((rt->rt_flags & (RTF_GATEWAY | RTF_LLINFO)) != RTF_LLINFO) {
 1655 fail:
 1656                 (void)nd6_free(rt);
 1657                 return NULL;
 1658         }
 1659         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1660         if (!ln)
 1661                 goto fail;
 1662         if (!rt->rt_gateway)
 1663                 goto fail;
 1664         if (rt->rt_gateway->sa_family != AF_LINK)
 1665                 goto fail;
 1666         sdl = SDL(rt->rt_gateway);
 1667 
 1668         olladdr = (sdl->sdl_alen) ? 1 : 0;
 1669         if (olladdr && lladdr) {
 1670                 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen))
 1671                         llchange = 1;
 1672                 else
 1673                         llchange = 0;
 1674         } else
 1675                 llchange = 0;
 1676 
 1677         /*
 1678          * newentry olladdr  lladdr  llchange   (*=record)
 1679          *      0       n       n       --      (1)
 1680          *      0       y       n       --      (2)
 1681          *      0       n       y       --      (3) * STALE
 1682          *      0       y       y       n       (4) *
 1683          *      0       y       y       y       (5) * STALE
 1684          *      1       --      n       --      (6)   NOSTATE(= PASSIVE)
 1685          *      1       --      y       --      (7) * STALE
 1686          */
 1687 
 1688         if (lladdr) {           /* (3-5) and (7) */
 1689                 /*
 1690                  * Record source link-layer address
 1691                  * XXX is it dependent to ifp->if_type?
 1692                  */
 1693                 sdl->sdl_alen = ifp->if_addrlen;
 1694                 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen);
 1695         }
 1696 
 1697         if (!is_newentry) {
 1698                 if ((!olladdr && lladdr)                /* (3) */
 1699                  || (olladdr && lladdr && llchange)) {  /* (5) */
 1700                         do_update = 1;
 1701                         newstate = ND6_LLINFO_STALE;
 1702                 } else                                  /* (1-2,4) */
 1703                         do_update = 0;
 1704         } else {
 1705                 do_update = 1;
 1706                 if (!lladdr)                            /* (6) */
 1707                         newstate = ND6_LLINFO_NOSTATE;
 1708                 else                                    /* (7) */
 1709                         newstate = ND6_LLINFO_STALE;
 1710         }
 1711 
 1712         if (do_update) {
 1713                 /*
 1714                  * Update the state of the neighbor cache.
 1715                  */
 1716                 ln->ln_state = newstate;
 1717 
 1718                 if (ln->ln_state == ND6_LLINFO_STALE) {
 1719                         /*
 1720                          * XXX: since nd6_output() below will cause
 1721                          * state tansition to DELAY and reset the timer,
 1722                          * we must set the timer now, although it is actually
 1723                          * meaningless.
 1724                          */
 1725                         ln->ln_expire = time_second + nd6_gctimer;
 1726 
 1727                         if (ln->ln_hold) {
 1728                                 /*
 1729                                  * we assume ifp is not a p2p here, so just
 1730                                  * set the 2nd argument as the 1st one.
 1731                                  */
 1732                                 nd6_output(ifp, ifp, ln->ln_hold,
 1733                                            (struct sockaddr_in6 *)rt_key(rt),
 1734                                            rt);
 1735                                 ln->ln_hold = NULL;
 1736                         }
 1737                 } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
 1738                         /* probe right away */
 1739                         ln->ln_expire = time_second;
 1740                 }
 1741         }
 1742 
 1743         /*
 1744          * ICMP6 type dependent behavior.
 1745          *
 1746          * NS: clear IsRouter if new entry
 1747          * RS: clear IsRouter
 1748          * RA: set IsRouter if there's lladdr
 1749          * redir: clear IsRouter if new entry
 1750          *
 1751          * RA case, (1):
 1752          * The spec says that we must set IsRouter in the following cases:
 1753          * - If lladdr exist, set IsRouter.  This means (1-5).
 1754          * - If it is old entry (!newentry), set IsRouter.  This means (7).
 1755          * So, based on the spec, in (1-5) and (7) cases we must set IsRouter.
 1756          * A quetion arises for (1) case.  (1) case has no lladdr in the
 1757          * neighbor cache, this is similar to (6).
 1758          * This case is rare but we figured that we MUST NOT set IsRouter.
 1759          *
 1760          * newentry olladdr  lladdr  llchange       NS  RS  RA  redir
 1761          *                                                      D R
 1762          *      0       n       n       --      (1)     c   ?     s
 1763          *      0       y       n       --      (2)     c   s     s
 1764          *      0       n       y       --      (3)     c   s     s
 1765          *      0       y       y       n       (4)     c   s     s
 1766          *      0       y       y       y       (5)     c   s     s
 1767          *      1       --      n       --      (6) c   c       c s
 1768          *      1       --      y       --      (7) c   c   s   c s
 1769          *
 1770          *                                      (c=clear s=set)
 1771          */
 1772         switch (type & 0xff) {
 1773         case ND_NEIGHBOR_SOLICIT:
 1774                 /*
 1775                  * New entry must have is_router flag cleared.
 1776                  */
 1777                 if (is_newentry)        /* (6-7) */
 1778                         ln->ln_router = 0;
 1779                 break;
 1780         case ND_REDIRECT:
 1781                 /*
 1782                  * If the icmp is a redirect to a better router, always set the
 1783                  * is_router flag. Otherwise, if the entry is newly created,
 1784                  * clear the flag. [RFC 2461, sec 8.3]
 1785                  */
 1786                 if (code == ND_REDIRECT_ROUTER)
 1787                         ln->ln_router = 1;
 1788                 else if (is_newentry) /* (6-7) */
 1789                         ln->ln_router = 0;
 1790                 break;
 1791         case ND_ROUTER_SOLICIT:
 1792                 /*
 1793                  * is_router flag must always be cleared.
 1794                  */
 1795                 ln->ln_router = 0;
 1796                 break;
 1797         case ND_ROUTER_ADVERT:
 1798                 /*
 1799                  * Mark an entry with lladdr as a router.
 1800                  */
 1801                 if ((!is_newentry && (olladdr || lladdr))       /* (2-5) */
 1802                  || (is_newentry && lladdr)) {                  /* (7) */
 1803                         ln->ln_router = 1;
 1804                 }
 1805                 break;
 1806         }
 1807 
 1808         /*
 1809          * When the link-layer address of a router changes, select the
 1810          * best router again.  In particular, when the neighbor entry is newly
 1811          * created, it might affect the selection policy.
 1812          * Question: can we restrict the first condition to the "is_newentry"
 1813          * case?
 1814          * XXX: when we hear an RA from a new router with the link-layer
 1815          * address option, defrouter_select() is called twice, since
 1816          * defrtrlist_update called the function as well.  However, I believe
 1817          * we can compromise the overhead, since it only happens the first
 1818          * time.
 1819          * XXX: although defrouter_select() should not have a bad effect
 1820          * for those are not autoconfigured hosts, we explicitly avoid such
 1821          * cases for safety.
 1822          */
 1823         if (do_update && ln->ln_router && !ip6_forwarding && ip6_accept_rtadv)
 1824                 defrouter_select();
 1825 
 1826         return rt;
 1827 }
 1828 
 1829 static void
 1830 nd6_slowtimo(ignored_arg)
 1831     void *ignored_arg;
 1832 {
 1833         int s = splnet();
 1834         int i;
 1835         struct nd_ifinfo *nd6if;
 1836 
 1837         callout_reset(&nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz,
 1838             nd6_slowtimo, NULL);
 1839         for (i = 1; i < if_index + 1; i++) {
 1840                 if (!nd_ifinfo || i >= nd_ifinfo_indexlim)
 1841                         continue;
 1842                 nd6if = &nd_ifinfo[i];
 1843                 if (nd6if->basereachable && /* already initialized */
 1844                     (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) {
 1845                         /*
 1846                          * Since reachable time rarely changes by router
 1847                          * advertisements, we SHOULD insure that a new random
 1848                          * value gets recomputed at least once every few hours.
 1849                          * (RFC 2461, 6.3.4)
 1850                          */
 1851                         nd6if->recalctm = nd6_recalc_reachtm_interval;
 1852                         nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable);
 1853                 }
 1854         }
 1855         splx(s);
 1856 }
 1857 
 1858 #define senderr(e) { error = (e); goto bad;}
 1859 int
 1860 nd6_output(ifp, origifp, m0, dst, rt0)
 1861         struct ifnet *ifp;
 1862         struct ifnet *origifp;
 1863         struct mbuf *m0;
 1864         struct sockaddr_in6 *dst;
 1865         struct rtentry *rt0;
 1866 {
 1867         struct mbuf *m = m0;
 1868         struct rtentry *rt = rt0;
 1869         struct sockaddr_in6 *gw6 = NULL;
 1870         struct llinfo_nd6 *ln = NULL;
 1871         int error = 0;
 1872 
 1873         if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
 1874                 goto sendpkt;
 1875 
 1876         if (nd6_need_cache(ifp) == 0)
 1877                 goto sendpkt;
 1878 
 1879         /*
 1880          * next hop determination.  This routine is derived from ether_outpout.
 1881          */
 1882         if (rt) {
 1883                 if ((rt->rt_flags & RTF_UP) == 0) {
 1884                         if ((rt0 = rt = rtalloc1((struct sockaddr *)dst, 1, 0UL)) !=
 1885                                 NULL)
 1886                         {
 1887                                 rt->rt_refcnt--;
 1888                                 if (rt->rt_ifp != ifp) {
 1889                                         /* XXX: loop care? */
 1890                                         return nd6_output(ifp, origifp, m0,
 1891                                                           dst, rt);
 1892                                 }
 1893                         } else
 1894                                 senderr(EHOSTUNREACH);
 1895                 }
 1896 
 1897                 if (rt->rt_flags & RTF_GATEWAY) {
 1898                         gw6 = (struct sockaddr_in6 *)rt->rt_gateway;
 1899 
 1900                         /*
 1901                          * We skip link-layer address resolution and NUD
 1902                          * if the gateway is not a neighbor from ND point
 1903                          * of view, regardless of the value of nd_ifinfo.flags.
 1904                          * The second condition is a bit tricky; we skip
 1905                          * if the gateway is our own address, which is
 1906                          * sometimes used to install a route to a p2p link.
 1907                          */
 1908                         if (!nd6_is_addr_neighbor(gw6, ifp) ||
 1909                             in6ifa_ifpwithaddr(ifp, &gw6->sin6_addr)) {
 1910                                 /*
 1911                                  * We allow this kind of tricky route only
 1912                                  * when the outgoing interface is p2p.
 1913                                  * XXX: we may need a more generic rule here.
 1914                                  */
 1915                                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 1916                                         senderr(EHOSTUNREACH);
 1917 
 1918                                 goto sendpkt;
 1919                         }
 1920 
 1921                         if (rt->rt_gwroute == 0)
 1922                                 goto lookup;
 1923                         if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
 1924                                 rtfree(rt); rt = rt0;
 1925                         lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1, 0UL);
 1926                                 if ((rt = rt->rt_gwroute) == 0)
 1927                                         senderr(EHOSTUNREACH);
 1928                         }
 1929                 }
 1930         }
 1931 
 1932         /*
 1933          * Address resolution or Neighbor Unreachability Detection
 1934          * for the next hop.
 1935          * At this point, the destination of the packet must be a unicast
 1936          * or an anycast address(i.e. not a multicast).
 1937          */
 1938 
 1939         /* Look up the neighbor cache for the nexthop */
 1940         if (rt && (rt->rt_flags & RTF_LLINFO) != 0)
 1941                 ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1942         else {
 1943                 /*
 1944                  * Since nd6_is_addr_neighbor() internally calls nd6_lookup(),
 1945                  * the condition below is not very efficient.  But we believe
 1946                  * it is tolerable, because this should be a rare case.
 1947                  */
 1948                 if (nd6_is_addr_neighbor(dst, ifp) &&
 1949                     (rt = nd6_lookup(&dst->sin6_addr, 1, ifp)) != NULL)
 1950                         ln = (struct llinfo_nd6 *)rt->rt_llinfo;
 1951         }
 1952         if (!ln || !rt) {
 1953                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0 &&
 1954                     !(nd_ifinfo[ifp->if_index].flags & ND6_IFF_PERFORMNUD)) {
 1955                         log(LOG_DEBUG,
 1956                             "nd6_output: can't allocate llinfo for %s "
 1957                             "(ln=%p, rt=%p)\n",
 1958                             ip6_sprintf(&dst->sin6_addr), ln, rt);
 1959                         senderr(EIO);   /* XXX: good error? */
 1960                 }
 1961 
 1962                 goto sendpkt;   /* send anyway */
 1963         }
 1964 
 1965         /* We don't have to do link-layer address resolution on a p2p link. */
 1966         if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
 1967             ln->ln_state < ND6_LLINFO_REACHABLE) {
 1968                 ln->ln_state = ND6_LLINFO_STALE;
 1969                 ln->ln_expire = time_second + nd6_gctimer;
 1970         }
 1971 
 1972         /*
 1973          * The first time we send a packet to a neighbor whose entry is
 1974          * STALE, we have to change the state to DELAY and a sets a timer to
 1975          * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do
 1976          * neighbor unreachability detection on expiration.
 1977          * (RFC 2461 7.3.3)
 1978          */
 1979         if (ln->ln_state == ND6_LLINFO_STALE) {
 1980                 ln->ln_asked = 0;
 1981                 ln->ln_state = ND6_LLINFO_DELAY;
 1982                 ln->ln_expire = time_second + nd6_delay;
 1983         }
 1984 
 1985         /*
 1986          * If the neighbor cache entry has a state other than INCOMPLETE
 1987          * (i.e. its link-layer address is already resolved), just
 1988          * send the packet.
 1989          */
 1990         if (ln->ln_state > ND6_LLINFO_INCOMPLETE)
 1991                 goto sendpkt;
 1992 
 1993         /*
 1994          * There is a neighbor cache entry, but no ethernet address
 1995          * response yet.  Replace the held mbuf (if any) with this
 1996          * latest one.
 1997          *
 1998          * This code conforms to the rate-limiting rule described in Section
 1999          * 7.2.2 of RFC 2461, because the timer is set correctly after sending
 2000          * an NS below.
 2001          */
 2002         if (ln->ln_state == ND6_LLINFO_NOSTATE)
 2003                 ln->ln_state = ND6_LLINFO_INCOMPLETE;
 2004         if (ln->ln_hold)
 2005                 m_freem(ln->ln_hold);
 2006         ln->ln_hold = m;
 2007         if (ln->ln_expire) {
 2008                 if (ln->ln_asked < nd6_mmaxtries &&
 2009                     ln->ln_expire < time_second) {
 2010                         ln->ln_asked++;
 2011                         ln->ln_expire = time_second +
 2012                                 nd_ifinfo[ifp->if_index].retrans / 1000;
 2013                         nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0);
 2014                 }
 2015         }
 2016         return(0);
 2017         
 2018   sendpkt:
 2019 
 2020 #ifdef MAC
 2021         mac_create_mbuf_linklayer(ifp, m);
 2022 #endif
 2023         if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
 2024                 return((*ifp->if_output)(origifp, m, (struct sockaddr *)dst,
 2025                                          rt));
 2026         }
 2027         return((*ifp->if_output)(ifp, m, (struct sockaddr *)dst, rt));
 2028 
 2029   bad:
 2030         if (m)
 2031                 m_freem(m);
 2032         return (error);
 2033 }       
 2034 #undef senderr
 2035 
 2036 int
 2037 nd6_need_cache(ifp)
 2038         struct ifnet *ifp;
 2039 {
 2040         /*
 2041          * XXX: we currently do not make neighbor cache on any interface
 2042          * other than ARCnet, Ethernet, FDDI and GIF.
 2043          *
 2044          * RFC2893 says:
 2045          * - unidirectional tunnels needs no ND
 2046          */
 2047         switch (ifp->if_type) {
 2048         case IFT_ARCNET:
 2049         case IFT_ETHER:
 2050         case IFT_FDDI:
 2051         case IFT_IEEE1394:
 2052 #ifdef IFT_L2VLAN
 2053         case IFT_L2VLAN:
 2054 #endif
 2055 #ifdef IFT_IEEE80211
 2056         case IFT_IEEE80211:
 2057 #endif
 2058         case IFT_GIF:           /* XXX need more cases? */
 2059                 return(1);
 2060         default:
 2061                 return(0);
 2062         }
 2063 }
 2064 
 2065 int
 2066 nd6_storelladdr(ifp, rt, m, dst, desten)
 2067         struct ifnet *ifp;
 2068         struct rtentry *rt;
 2069         struct mbuf *m;
 2070         struct sockaddr *dst;
 2071         u_char *desten;
 2072 {
 2073         int i;
 2074         struct sockaddr_dl *sdl;
 2075 
 2076         if (m->m_flags & M_MCAST) {
 2077                 switch (ifp->if_type) {
 2078                 case IFT_ETHER:
 2079                 case IFT_FDDI:
 2080 #ifdef IFT_L2VLAN
 2081         case IFT_L2VLAN:
 2082 #endif
 2083 #ifdef IFT_IEEE80211
 2084                 case IFT_IEEE80211:
 2085 #endif
 2086                         ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr,
 2087                                                  desten);
 2088                         return(1);
 2089                 case IFT_IEEE1394:
 2090                         /*
 2091                          * netbsd can use if_broadcastaddr, but we don't do so
 2092                          * to reduce # of ifdef.
 2093                          */
 2094                         for (i = 0; i < ifp->if_addrlen; i++)
 2095                                 desten[i] = ~0;
 2096                         return(1);
 2097                 case IFT_ARCNET:
 2098                         *desten = 0;
 2099                         return(1);
 2100                 default:
 2101                         m_freem(m);
 2102                         return(0);
 2103                 }
 2104         }
 2105 
 2106         if (rt == NULL) {
 2107                 /* this could happen, if we could not allocate memory */
 2108                 m_freem(m);
 2109                 return(0);
 2110         }
 2111         if (rt->rt_gateway->sa_family != AF_LINK) {
 2112                 printf("nd6_storelladdr: something odd happens\n");
 2113                 m_freem(m);
 2114                 return(0);
 2115         }
 2116         sdl = SDL(rt->rt_gateway);
 2117         if (sdl->sdl_alen == 0) {
 2118                 /* this should be impossible, but we bark here for debugging */
 2119                 printf("nd6_storelladdr: sdl_alen == 0\n");
 2120                 m_freem(m);
 2121                 return(0);
 2122         }
 2123 
 2124         bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
 2125         return(1);
 2126 }
 2127 
 2128 static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS);
 2129 static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS);
 2130 #ifdef SYSCTL_DECL
 2131 SYSCTL_DECL(_net_inet6_icmp6);
 2132 #endif
 2133 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
 2134         CTLFLAG_RD, nd6_sysctl_drlist, "");
 2135 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
 2136         CTLFLAG_RD, nd6_sysctl_prlist, "");
 2137 
 2138 static int
 2139 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
 2140 {
 2141         int error;
 2142         char buf[1024];
 2143         struct in6_defrouter *d, *de;
 2144         struct nd_defrouter *dr;
 2145 
 2146         if (req->newptr)
 2147                 return EPERM;
 2148         error = 0;
 2149 
 2150         for (dr = TAILQ_FIRST(&nd_defrouter);
 2151              dr;
 2152              dr = TAILQ_NEXT(dr, dr_entry)) {
 2153                 d = (struct in6_defrouter *)buf;
 2154                 de = (struct in6_defrouter *)(buf + sizeof(buf));
 2155 
 2156                 if (d + 1 <= de) {
 2157                         bzero(d, sizeof(*d));
 2158                         d->rtaddr.sin6_family = AF_INET6;
 2159                         d->rtaddr.sin6_len = sizeof(d->rtaddr);
 2160                         if (in6_recoverscope(&d->rtaddr, &dr->rtaddr,
 2161                             dr->ifp) != 0)
 2162                                 log(LOG_ERR,
 2163                                     "scope error in "
 2164                                     "default router list (%s)\n",
 2165                                     ip6_sprintf(&dr->rtaddr));
 2166                         d->flags = dr->flags;
 2167                         d->rtlifetime = dr->rtlifetime;
 2168                         d->expire = dr->expire;
 2169                         d->if_index = dr->ifp->if_index;
 2170                 } else
 2171                         panic("buffer too short");
 2172 
 2173                 error = SYSCTL_OUT(req, buf, sizeof(*d));
 2174                 if (error)
 2175                         break;
 2176         }
 2177         return error;
 2178 }
 2179 
 2180 static int
 2181 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
 2182 {
 2183         int error;
 2184         char buf[1024];
 2185         struct in6_prefix *p, *pe;
 2186         struct nd_prefix *pr;
 2187 
 2188         if (req->newptr)
 2189                 return EPERM;
 2190         error = 0;
 2191 
 2192         for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
 2193                 u_short advrtrs;
 2194                 size_t advance;
 2195                 struct sockaddr_in6 *sin6, *s6;
 2196                 struct nd_pfxrouter *pfr;
 2197 
 2198                 p = (struct in6_prefix *)buf;
 2199                 pe = (struct in6_prefix *)(buf + sizeof(buf));
 2200 
 2201                 if (p + 1 <= pe) {
 2202                         bzero(p, sizeof(*p));
 2203                         sin6 = (struct sockaddr_in6 *)(p + 1);
 2204 
 2205                         p->prefix = pr->ndpr_prefix;
 2206                         if (in6_recoverscope(&p->prefix,
 2207                             &p->prefix.sin6_addr, pr->ndpr_ifp) != 0)
 2208                                 log(LOG_ERR,
 2209                                     "scope error in prefix list (%s)\n",
 2210                                     ip6_sprintf(&p->prefix.sin6_addr));
 2211                         p->raflags = pr->ndpr_raf;
 2212                         p->prefixlen = pr->ndpr_plen;
 2213                         p->vltime = pr->ndpr_vltime;
 2214                         p->pltime = pr->ndpr_pltime;
 2215                         p->if_index = pr->ndpr_ifp->if_index;
 2216                         p->expire = pr->ndpr_expire;
 2217                         p->refcnt = pr->ndpr_refcnt;
 2218                         p->flags = pr->ndpr_stateflags;
 2219                         p->origin = PR_ORIG_RA;
 2220                         advrtrs = 0;
 2221                         for (pfr = pr->ndpr_advrtrs.lh_first;
 2222                              pfr;
 2223                              pfr = pfr->pfr_next) {
 2224                                 if ((void *)&sin6[advrtrs + 1] >
 2225                                     (void *)pe) {
 2226                                         advrtrs++;
 2227                                         continue;
 2228                                 }
 2229                                 s6 = &sin6[advrtrs];
 2230                                 bzero(s6, sizeof(*s6));
 2231                                 s6->sin6_family = AF_INET6;
 2232                                 s6->sin6_len = sizeof(*sin6);
 2233                                 if (in6_recoverscope(s6,
 2234                                     &pfr->router->rtaddr,
 2235                                     pfr->router->ifp) != 0)
 2236                                         log(LOG_ERR,
 2237                                             "scope error in "
 2238                                             "prefix list (%s)\n",
 2239                                             ip6_sprintf(&pfr->router->rtaddr));
 2240                                 advrtrs++;
 2241                         }
 2242                         p->advrtrs = advrtrs;
 2243                 } else 
 2244                         panic("buffer too short");
 2245 
 2246                 advance = sizeof(*p) + sizeof(*sin6) * advrtrs;
 2247                 error = SYSCTL_OUT(req, buf, advance);
 2248                 if (error)
 2249                         break;
 2250         }
 2251         return error;
 2252 }

Cache object: 183f53448e995e6d8128e8cdc76ecdad


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.